Proceedings of SPIE - the International Society for Optical Engineering
Surface phonon polaritons, SPhPs, result from the coupling or interaction of light with a phonon resonance. There has been extensive research into utilizing surface plasmon polaritons, SPPs, for subwavelength confinement of propagating waveguide modes for photonic integrated circuits. This work investigates the use of a multilayer system or insulatormetal-insulator (IMI) heterostructure as a SPhP-enhanced infrared waveguide where the metal response is due to phonons in a polar dielectric's Reststrahlen band. In addition, an IMI heterostructure supports types of modes: An even mode and odd mode that have their own unique trade-offs. For the odd mode as the metal film thickness decreases the confinement of the SPhPs decreases, and thus resulting in an increase in the SPhPs propagation length. Conversely, the even mode shows the opposite behavior with decreasing metal film where the confinement increases as propagation length decreases. This endeavor investigates the trade-off between the even and odd IMI modes, and the characterization of propagation length and model confinement, as applied to a hybrid phononic waveguide.
Al-Amri, A., Finch, M. F., Barreto Saunders Filho, C. A., & Lail, B. A. (2017). A hybrid phononic waveguide using multilayer structure at mid-infrared. Paper presented at the Proceedings of SPIE - the International Society for Optical Engineering, , 10343 doi:10.1117/12.2274153